The invention relates to sound activated liquid display devices, such as lamps.
Liquid display lamps of the general type which comprise a liquid container with a transparent wall portion in which two immiscible liquids having different visual characteristics and specific gravities or densities are mingled or merged for viewing through the wall portion to provide an interesting visual effect are well known and have been sold worldwide in large numbers for very many years.
U.S. Pat. No. 3,387,396, issued 1968 to Smith, the disclosure of which is incorporated herein by reference, describes one version in which the first, denser liquid can be a wax or jelling agent having a melting point above ambient/room temperature and normally resting as a mass at the bottom so that a portion thereof melts when heated from below by the lamp bulb, forming one or more globules of reduced density which separate, floating up into circulation and temporary suspension in the first liquid before cooling and falling back to the bottom of the container to coalesce with the remainder of the second liquid mass.
The rate of separation and mingling of the denser liquid with the less dense liquid is substantially constant as a constant heat source is taught, but could not change/react quickly even if a variable heat source were utilized as heat transfer rates are inherently relatively slow.
It is an object of the invention to provide a sound activated liquid display device in which the rate of mingling of two or more immiscible liquids of different densities and visual characteristics changes quickly in response to sounds, for example, music and voices.
According to one aspect, the invention provides a display device comprising a liquid container with a transparent wall portion containing two immiscible liquids having different visual characteristics and different specific gravities or densities and/or different viscosities and means responsive to changes in one or more sound parameters in the vicinity of the device, such as changes in volume or frequency, for injecting/circulating/mingling one liquid into another at rates related to the sound changes, for viewing through the wall portion to provide an interesting visual effect that reacts to music or voices.
One liquid can be injected into the other for dispersion and suspension therein as one or more distinct globules at rates and sizes determined by deviations from ambient sound levels.
The introduction of one or more liquids into another may be accomplished by one or more respective pumps, valves, injectors, or gravity-fed devices. Thus, a less dense liquid may be injected downwards into a denser liquid from the top, subsequently floating to the top, and a denser liquid may be injected upwards from the bottom, subsequently sinking. The immiscible liquids may, for example, be oil and water and, usually, more colored liquids are injected into less colored or clear liquids. By using multiple liquids and injecting means, a display with great, even rhythmic, movement can be produced with each liquid of a different specific gravity or viscosity reacting to a different sound frequency and or sound level.
The display device may include a lamp and means may also be provided to change the level of illumination provided by the lamp in response to changes in one or more sound parameters in the vicinity of the device.
Thus, the display device may include one or more pumps and/or valves that are controlled by an electronic circuit which includes: a microphone, pre-amp, AGC, selective frequency filters and motor and illumination control circuit.
According to another aspect, the invention provides a method of providing a liquid display by co-mingling immiscible liquids of different appearances at rates determined by changes in sound parameters particularly in the audio range.